Graham questioned President Obama’s decision to release the “Taliban Dream Team” from the Guantánamo Bay detention camp in exchange for Bergdahl, a 28-year-old Army sergeant who spent five years as a prisoner of the militant Haqqani network.

“While I appreciate an American was released from captivity, this decision by the Obama administration has serious implications for our future national security,” Graham wrote.

He predicted the militants released from American custody, including the chief of staff of the Taliban army and Taliban’s deputy minister of intelligence, will return to the fight “surely as night follows day.”

“I fear President Obama’s decision will inevitably lead to more Americans being kidnapped and held hostage throughout the world,” he said.

Graham questioned why the administration did not notify Congress 30 days in advance of the release of prisoners from Guantánamo as required the by the National Defense Authorization Act.

“We need a thorough review of this decision, and I urge you to hold a hearing on this matter as it has profound implications for national security,” he said.

Graham faces a crowed field of challengers in the South Carolina Republican primary scheduled for June 10.

Sen. James Inhofe (Okla.), the senior Republican on the Senate Armed Services panel, and Rep. Buck McKeon (Calif.), the chairman of the House Armed Services Committee, released a statement over the weekend calling for a careful examination of the deal that secured Bergdahl’s release.